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If enabled, if any email addresses in FROM:, TO:, CC: are not Jira users then JEMH will create users with their Personal Name and Email Address.
For more info about creating users see: Enable non-Jira account holders User Creation
User Directory
Defines the User Directory to add the newly created user to. Use the DEFAULT (first available writable directory in the Jira User Directories list) OR pick a specific directory.
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